| 摘要 |
PCT No. PCT/SE96/00561 Sec. 371 Date Nov. 5, 1997 Sec. 102(e) Date Nov. 5, 1997 PCT Filed Apr. 29, 1996 PCT Pub. No. WO96/35240 PCT Pub. Date Nov. 7, 1996An antenna element intended for transmission and reception of orthogonal polarizations having a good polarization purity of electomagnetic radiation is described. It comprises a ground plane (2) and at least one radiation disc (1) connected to two ports (4, 5) for the supply of a desired electromagnetic radiation, preferably in the microwave range. The distance between the ground plane (2) and the radiation disc (1) is a fraction of the wavelength lambda of the radiation. The antenna element is in particular characterized in that the ports (4, 5) are located at an electric distance of 90 DEG from each other and that a quarterwave transformer (6) is added between the ground plane (2) and the radiation disc (1) that is shaped so that the transmission line impedance between the ports (4, 5) is reduced in order to make the ports radiationally independent of each other. |
